Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(?:(Dim|Public|Private) )(?:(WithEvents) )?(?:(?:(?!Declare)(?!Type)(?!Enum)(?!Const)(\w*))(\(\))?)(?: As )?(?:(New) )?(\w*)(, [\w ,\(\)]*)?" test_str = ("Attribute VB_Name = \"mdl_WbkInits\"\n" "Option Compare Database\n\n" "Public WithEvents ue_u23 As New String, soumeth_34ing as somethnig, asi As Anthere item, Maybe lastOne \n" "Public ueu As Variant\n" "Dim ueu\n\n" "Public Declare Function IIDFromString Lib \"ole32\" (ByVal lpsz As Long, ByRef lpiid As UUID) As Long\n" "Private Declare Function IIDFromString Lib \"ole32\" (ByVal lpsz As Long, ByRef lpiid As UUID) As Long\n\n" "Private Declare PtrSafe Function FindWindowEx Lib \"user32\" Alias \"FindWindowExA\" (ByVal hWnd1 As Long, ByVal hwnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long\n\n" "Private Type UUID 'GUID\n" " Data1 As Long\n" " Data2 As Integer\n" " Data3 As Integer\n" " Data4(7) As Byte\n" "End Type\n\n" "Public Enum e_ControlEventCatch\n" " e_onClick\n" " e_onChange\n" " e_onUpdate\n" " e_onUpdated\n" " e_onDblClick\n" " e_onFocus\n" " e_onExtClick\n" " e_onExtDblClick\n" " e_onActivate\n" " e_onDeActivate\n" "End Enum\n\n" "Public Const IID_IDispatch As String = \"{00020400-0000-0000-C000-000000000046}\"\n" "Const OBJID_NATIVEOM As Long = &HFFFFFFF0\n") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html